Aquatic Birds are designed to be adapted to a very watery environment. Perhaps one of the most well known and well adapted of birds is the penguin. Penguins have heavy solid bones which enable them to stay underwater, and wings which resemble flippers, unlike all other birds which have quilled wings, and enable the penguin to �fly� underwater at speeds which reach up to 15 mph. One of the most obvious and needed adaptations for almost all aquatic birds (especially penguins who spend on average 75% of their lives in the water) is a layer of waterproofing. The feathers on aquatic birds are especially useful for keeping them dry and warm. The feathers are usually adapted to be stiff and tightly packed, and in the case of the penguin, are coated with oil from the preen gland which increases impermeability. All marine birds have a preen gland but secrete different fats and waxes which prevent it from getting wet when it enters the water. Most marine birds have a third and final method of waterproofing, by releasing keratin dust (waterproof) into the bird�s feathers.
Aquatic and marine birds can be broken down into 3 main classifications. The first are Sphenisciformes (penguins). Although I have already mentioned some of the major points of the penguin�s adaptations to a cold and watery environment, there are some nicer points which I wish to elaborate on. Directly under the streamlined plumage, the penguin has a trapped layer of air which is its first defence against the freezing sea water. The penguin carries a thick layer of insulating blubber next to its skin which slows down heat loss in a cold environment. A remarkable heat exchange system prevents the blood entering the core from being too cold. Black and white countershading on the penguins� bodies makes them nearly invisible to predators from above and below. The penguin�s short feet near the back of its body and strong, thick bones make it perfect for diving to catch its prey.
The second type of aquatic bird is classified as anseriformes or waterfowl. These consist mainly of ducks, geese and swans.
